Sealing apparatus

Claim 1

IN COMBINATION, AN INNER MEMBER MOUNTED FOR RECIPROCATION IN A BORE OF AN OUTER MEMBER, A FLUID RECEIVING CHAMBER ASSOCIATED WITH SAID MEMBERS, SAID OUTER MEMBER HAVING FIRST AND SECOND ANNULAR GROOVES OPEN TO SAID BORE AT SPACED POINTS, SAID FIRST GROOVE BEING IN COMMUNICATION WITH SAID CHAMBER, A SOFT RESILENT RUBBERLIKE SEALING RING WITHIN SAID FIRST GROOVE AND HAVING A FLEXIBLE FLUID PRESSURE RESPONSIVE LIP IN SUBSTANTIAL SEALING CONTACT WITH SAID INNER MEMBER, A SOFT RESILIENT RUBBERLIKE WIPING RING WITHIN SAID SECOND GROOVE IN CONTACT WITH SAID INNER MEMBER AND ADAPTED TO WIPE SUBSTANTIALLY ALL FLUID FROM THE PORTION OF SAID INNER MEMBER PASSING OUTWARDLY THERETHROUGH DURING RECIPROCATION OF SAID INNER MEMBER, A CLOSED HOLLOW SPACE IN SAID OUTER MEMBER AND OPEN TO SAID BORE BETWEEN SAID RINGS AND ADAPTED TO RECEIVE FLUID PASSING SAID SEALING RING FROM SAID CHAMBER AND WIPED FROM THE ROD BY SAID WIPING RING, SAID HOLLOW SPACE HAVING PORTIONS COMMUNICATING WITH BOTH SAID FIRST AND SECOND GROOVES AND BEING OPEN TO BOTH GROOVES FOR THE PASSAGE OF FLUID THEREBTWEEN IN BOTH DIRECTIONS, SAID LIP BEING ADAPTED TO LIFT AWAY FROM SAID INNER MEMBER TO PERMIT RETURN OF FLUID FROM SAID SPACE TO SAID CHAMBER WHEN THE PRESSURE OF FLUID WITHIN SAID SPACE IS GREATER THAN THE PRESSURE OF FLUID WITHIN SAID CHAMBER, SAID SECOND GROOVE HAVING A FIXED END WALL SUBSTANTIALLY AT RIGHT ANGLES TO THE AXIS OF SAID BORE AND UNYIELDINGLY SUPPORTING SAID WIPING RING ACROSS THE GREATEST PORTION OF THE LATTER''S TRANSVERSE THICKNESS FOR EFFECTIVELY RETAINING SAID WIPING RING WITHIN SAID SECOND GROOVE AGAINST PRESSURE OF FLUID WITHIN SAID SPACE.